RU2266646C1 - Herbicidal composition - Google Patents

Abstract

FIELD: organic chemistry, agriculture.

SUBSTANCE: claimed composition contains (mass %): 2,4-dichlorophenoxyacetic acid 2-ethylehexyl ester 35-77; 2-methoxy-3,6,-dichlorobenzoic acid 2-ethylehexyl ester 5-11; surfactant 5-7.5; and balance: solvent.

EFFECT: herbicidal composition with increased storage stability and improved effectiveness in respect to wide range of weeds, including sow-thistle.

2 cl, 5 tbl, 16 ex

Description

The invention relates to agriculture, namely to chemical plant protection products used to control weeds in crops of grain crops, including perennial root weeds, such as yellow thistle (field sow thistle) and pink thistle (field thistle).

The most common and widely used for these purposes are herbicides based on 2,4-dichlorophenoxyacetic acid (2,4-D) and 2-methoxy-3,6-dichlorobenzoic acid (dicamba), their salts and esters, as well as their mixtures or mixtures with other herbicides (Melnikov NN and others. "Guide to pesticides." - M .: Chemistry, 1995, S. 58-62, 66).

Known herbicidal composition based on 2,4-D and dicamba (UK Patent No. 1058314), which is used to control amaranth, field mustard, mountaineer at a consumption rate of 0.75-1.2 kg / ha. With a decrease in the consumption rate, this composition has a low herbicidal activity.

Known herbicidal compositions containing derivatives of 2,4-dichlorophenoxyacetic acid, including its esters, and derivatives of 2-methoxy-3,6-dichlorobenzoic acid, including its esters, surfactants and diluent (US patent No. 3297427). Compositions have low storage stability and have a limited range of weed control.

The advantage of 2,4-D esters and dicamba over other derivatives of these acids is that they penetrate into plants faster, and therefore their use is less dependent on weather conditions. After penetration into the leaves of plants, esters are rapidly and to a large extent hydrolyzed to free acids (G. Mayer-Bode, “Herbicides and their residues.” - M .: Mir, 1972, p. 87).

Closest to the claimed composition is a herbicidal composition based on n-C ₇ -C ₉ esters of 2,4-D and H-C ₇ -C ₉ esters of dicamba containing 56-74 wt.% Esters of 2,4-D and 6, 6-15.4 wt.% Dicamba esters, 12-20% surfactants and a solvent. As a surfactant, ethoxylated alkyl phenols or mixtures thereof with sodium alkyl benzene sulfonate are used, and a petroleum solvent is used as a solvent (RF patent No. 2072226).

The disadvantage is the use of a large number of surfactants, especially hydroxyethylated alkyl phenols. These substances have poor biodegradability (30-40% within 2-3 days), which has an adverse effect on the environment (see Abstracts of reports to the Fifth All-Union Conference “Surface-active substances and raw materials for them”, Schebekino, September 17-21, 1979, the report "Replacement of OP-7 and OP-10 in herbicidal compositions with biologically soft surfactants" Gazizov RT, Yurenkov VA, Davydov AM, Bazunova GG Reference "Surface active substances ", Leningrad," Chemistry ", Leningrad Branch, 1979, p. 285, 305, 306).

With a decrease in the amount of surfactant to 12-15%, a significant decrease in the stability of the emulsion is observed. In addition, the drug is ineffective against perennial root weeds such as yellow thistle (field sow thistle) and pink thistle (field thistle). It is known that with these weeds littered with wheat in the amount of 15-20 sprouts per m ^{2, the} yield reduction can reach 36% (Canada Thistle and Perennial Sow-thistle. Control in direct Seeding Systems. Agriculture, Food and Rural Development, 2003, p.2).

A known herbicidal composition for controlling perennial root weeds containing a derivative of chlorophenoxyacetic acid, including n-C ₇ -C ₉ esters of 2,4-D, in an amount of 12-43 wt.% And synergist - N-cyclohexanone-O- ( 2-methoxy-3,6-dichlorobenzoyl) oxime in an amount of 10-20 wt.%, Ethoxylated alkyl phenol 15-20 wt.% And a solvent. The drug is used to inhibit the growth of pink sow thistle in wheat crops at a dose of 0.9 kg / ha, and in corn crops at a dose of 0.6 kg / ha (RF patent No. 2073973).

The object of the present invention is a herbicidal composition containing 35.0-77.0 wt.% 2-ethylhexyl ester of 2,4-dichlorophenoxyacetic acid (2,4-D) (I) and 5.0-11.0 wt.% 2 2-methoxy-3,6-dichlorobenzoic acid-ethylhexyl ester (dicamba) (II) with an I: II ratio of 7: 1 to 6: 1, a mixture of nonionic and anionic surfactants in a ratio of 1 ÷ (1.5-2 ) in an amount of 5-7.5 wt.% and an organic solvent. Ethoxylated castor oil is used as a nonionic surfactant, and calcium dodecylbenzenesulfonate as anionic surfactant. As solvents, kerosene or xylene is used, in which 2,4-D 2-ethylhexyl esters and dicamba are dissolved indefinitely.

Unlike ethoxylated alkyl phenols, ethoxylated castor oil is biodegradable (up to 90% during the first 3-5 hours) and therefore does not cause any harm to the environment (Surfactants Handbook, Leningrad, Chemistry, Leningrad Branch, 1979, p. 279-280).

In contrast to the composition of the prototype, in the new composition, the active substances used are not mixtures of C ₇ -C ₉ ethers of normal structure, but 2-ethylhexyl ethers 2,4-D and dicamba. These esters have a higher solubility, which allows the use of a smaller amount of surfactants to obtain stable emulsions. In addition, the properties of the drug do not depend on the composition of the alcohol component, which can vary over a fairly wide range.

The new composition has a higher storage stability and higher herbicidal activity compared with the composition of the prototype.

It is especially important that the composition in accordance with the present invention suppresses harmful weeds such as yellow thistle and pink thistle in spring wheat crops. The efficiency reaches 97%, while the effectiveness of the composition of the prototype under the same conditions does not exceed 75%. The effectiveness of the new drug can be increased due to the additional inclusion of a small amount of oil, for example, industrial oil. The addition of industrial oil to the formulation, as shown by experiments, increases the adherence of the drug to the treated surface and its retention time on it and has the effect of increasing herbicidal activity. To suppress weeds in spring wheat crops, the rate of consumption of the drug per active substance (i.e. acid) should be at least 300 g / ha. As for the dose of 250 g / ha in barley indicated in the prototype, it is suitable for taking into account weed growth inhibition and calculating the synergistic effect, but not as a working dose for effective weed control in crops of grain crops, especially such as yellow thistle and pink thistle . (See “List of pesticides and agrochemicals approved for use in the territory of the Russian Federation”, 2003, p. 206)

The presence of a synergistic effect for mixtures of derivatives, including 2,4-D (I) and dicamba (II) esters in various ratios of I: II (from 1: 1 to 8: 1), was previously established (US patent No. 3297427).

The introduction of certain components in the preparative form can change for better or worse the effectiveness of the drug, but not the synergy coefficient, the value of which depends on the ratio of active substances and is individual for each biological object.

Thus, subject to the optimal ratio of active substances (from 6: 1 to 7: 1) due to the use of 2-ethylhexyl ethers 2,4-D and dicamba instead of C ₇ -C ₉ ethers of normal structure and a new combination of nonionic and anionic surface active substances, namely ethoxylated castor oil and calcium dodecylbenzenesulfonate in a ratio of 1: (1.5-2) and the use of such available organic solvents as kerosene and xylene, it was possible to obtain a herbicidal composition that has significant advantages in comparison the prototype both in storage stability, and efficacy against a broad spectrum of weeds, including malware such as sow thistle and sow thistle yellow pink.

The effectiveness of the composition can be significantly improved by adding a small amount (~ 2%) of industrial oil, which was manifested in experiments with perennial root weeds.

Example 1

67.5 g of 2,4-D 2-ethylhexyl ether is dissolved in 15.0 g of kerosene, 10 g of dicamba 2-ethylhexyl ether, 3 g of ethoxylated castor oil and 4.5 g of calcium dodecylbenzenesulfonate are added thereto. The mixture is heated to 35-40 ° C, stirred for 10-15 minutes and cooled to room temperature. 2.0 g of the obtained preparation is mixed with 98.0 g of water, poured into a sump, turned over 12 times, kept at a temperature of 20 ° C for 4 hours and the amount of sludge is determined. The particle size is determined using a microsizer 201A.

Example 2

67.5 g of 2,4-D 2-ethylhexyl ether, 10.9 g of dicamba 2-ethylhexyl ether are dissolved in 14.1 g of xylene, 3 g of ethoxylated castor oil and 4.5 g of calcium dodecylbenzenesulfonate are added thereto, and then in example 1.

Example 3

67.5 g of 2,4-D 2-ethylhexyl ether, 10.9 g of dicamba 2-ethylhexyl ether are dissolved in 14.1 g of kerosene, 3.0 g of ethoxylated castor oil and 4.5 g of dodecylbenzenesulfonate are added, and further, as in example 1.

Example 4

67.5 g of 2,4-D 2-ethylhexyl ether is dissolved in 15.0 g of xylene, 10 g of dicamba 2-ethylhexyl ether, 3.0 g of ethoxylated castor oil and 4.5 g of calcium dodecylbenzenesulfonate are added thereto, and further in example 1.

Example 5

77.0 g of 2,4-D 2-ethylhexyl ether and 11.0 g of dicamba 2-ethylhexyl ether are dissolved in 7.0 g of kerosene, 2.0 g of ethoxylated castor oil and 3 g of calcium dodecylbenzenesulfonate are added, and further, as in the example 1.

Example 6

55.6 g of 2,4-D 2-ethylhexyl ether and 8.4 g of dicamba 2-ethylhexyl ether are dissolved in 28.5 g of xylene, 3.0 g of ethoxylated castor oil and 4.5 g of calcium dodecylbenzenesulfonate are added, and further in example 1.

Example 7

44.4 g of 2,4-D 2-ethylhexyl ether and 6.7 g of dicamba 2-ethylhexyl ether are dissolved in 41.4 g of kerosene, 2.5 g of ethoxylated castor oil and 5 g of calcium dodecylbenzenesulfonate are added, and further, as in the example 1.

Example 8

44.4 g of 2,4-D 2-ethylhexyl ether are dissolved in 45.9 g of xylene, 6.7 g of dicamba 2-ethylhexyl ether, 1.0 g of ethoxylated castor oil and 2 g of calcium dodecylbenzenesulfonate are added, and further, as in the example 1.

Example 9

35.0 g of 2,4-D 2-ethylhexyl ether is dissolved in 55.0 g of xylene, then 5 g of dicamba 2-ethylhexyl ether, 2.0 g of ethoxylated castor oil and 3 g of calcium dodecylbenzenesulfonate are added thereto, and further, as in example 1.

Example 10

67.5 g of 2,4-D 2-ethylhexyl ether and 10.0 g of dicamba 2-ethylhexyl ether are dissolved in 13.0 g of kerosene, then 2.0 g of industrial oil I-8A, 3.0 g of ethoxylated castor oil are added and 4.5 g of calcium dodecylbenzenesulfonate and further, as in example 1.

Example 11

67.5 g of 2,4-D 2-ethylhexyl ether are dissolved in 13.0 g of xylene, 10.0 g of dicamba 2-ethylhexyl ether, 2.0 g of industrial oil I-8A, 3.0 g of ethoxylated castor oil are added and 4.5 g of calcium dodecylbenzenesulfonate and further, as in example 1.

Physico-chemical properties of the drug and its formulations are presented in table 1. As can be seen from the table, the stability of the emulsion of the drug of the proposed composition is higher than that of the prototype.

Example 12. Assessment of drug retention.

A 0.5% and 0.25% emulsion is prepared from the preparation, which is used to treat the surface of the plates until completely wetted, held for 1 hour, put the plate in an upright position and determine the amount of preparation remaining on the plates. The results are presented in table 2.

Example 13

Field trials of the compositions were carried out on spring wheat cultivars of the Smena variety in the Odintsovo district of the Moscow region by the Department of Agriculture of the SRIH TsRNZ.

The experimental plots are clogged with yellow sow thistle (perennial) and medicinal haze, middle starlet, white gauze, shepherd’s bag, chickweed picnic, tenacious scallop, odorless tripe, field furrow, purple purulent (annual). The plot area is 25 m ² . Clogging density 230-320 pcs./m ² .

The preparations were used at the time of tillering of the crop and in the phase of 2-4 true leaves at annuals and the rosette phase at perennial weeds.

The soil is medium loamy, containing humus 1.9-2.1%; pH 5.8; P ₂ O ₅ - 335 mg / kg; K ₂ O - 180 mg / kg of soil.

The seeding rate of 500 grains per 1 m ² .

The first count was carried out before treatment with the preparations, the second count 7 days after the treatment, the third 30 days after the treatment and the last count before harvesting 40 days after the third count. The results were summarized.

A prototype of a stalemate was taken as a reference. RF №2072226, Dialen * (* Dialen - 2,4-D + dicamba (diethylamine salts)), Esteron ** (** Esteron - 2-ethylhexyl ether 2,4-D) at a rate of 300 g / ha per d .in.

Four repetition.

The results of field tests on spring wheat (the average of 4 replicates) are presented in table 3. According to the test results, we can conclude that the proposed herbicidal composition is more effective than the standard.

Example 14

The tests were carried out at the Kochkovskoye farm in the Kochkovsky district of the Novosibirsk region from June to September 2004. Altai 98 varieties of spring wheat were weed with herbicides, weed by field butcher, field sow thistle and field bindweed during the tillering phase. The size of the plots is 1.8 ha. The phase of development of harmful objects: field calf and field thistle - rosette of 4-5 leaves, field bindweed - shoots of 15-20 cm. The average number of weeds before treatment is 10.8 ind. on 1 m ² , on the 30th day after treatment - 0.8 ind./m ² . The effectiveness of the compounds was determined by reducing the number of each species

root shoot weeds in %% to control (average of 4 replicates). In the same conditions, tests were taken taken as a prototype composition according to the patent of the Russian Federation No. 2072226 (example 1). Accounting for the crop was carried out by the continuous harvesting method. The results are presented in table 4.

Example 15

The tests were carried out on the experimental field of the Kurgan State Agricultural Agricultural Academy in the crops of spring wheat of the Tertsiya variety. Treatment with herbicides was carried out manually in the tillering phase of the culture. The phase of development of harmful objects: field calf, field sow thistle - rosette - 4-5 leaves; field bindweed - shoots of 15-20 cm. The tests were carried out in conditions of severe drought and against the background of high infection with root-weed species of weeds. In the total weight of the control (94 ind./m ² ), field sow thistle was 56%, field bindweed was 30%, and field thistle was 14%. The size of the plots is 15 m ² , the repetition is fourfold. As a reference used Banvel D.

Biological effectiveness was determined by reducing the number of weeds according to the formula

where a is the number of weeds in the control;

b - the number of weeds after treatment on the 30th day of accounting.

The results of the experiments are presented in table 4.

As can be seen from the presented results, the new herbicidal composition is highly effective for protecting spring wheat from weeds, including perennial root weeds, and is superior in effectiveness to the prototype preparations.

Example 16

Tests of the herbicidal activity of the compositions were carried out in a greenhouse in the vegetation vessels on spring wheat crops. The herbicidal efficacy of the compositions was determined on a mixture of dicotyledonous weeds: tar, radish, shiritsa, shepherd’s bag, field yarut, white gauze and others. Herbicide treatment was carried out in the phase of the beginning of tillering of wheat. Accounting for the effectiveness of the compositions was carried out 20 days after their introduction to inhibition of the weight of the wet mass of weeds in comparison with the control. At the same time, the selectivity of the compounds with respect to wheat was evaluated. The repetition for each option is 4-fold. The synergistic effect was calculated by the formula Popov P.V. (Chemistry in Agriculture, 1976, No. 11, p. 54-55). For this purpose, the doses causing 90% inhibition of weed weight (SK ₉₀ ) were determined and the joint action coefficient (KSD) was calculated, which is the quotient of dividing the calculated value of SK ₉₀ by the corresponding experimental value. Values of KSD greater than unity indicate the presence of synergy in the mixture, equal to unity — additive effect, less than unity — antagonistic effect.

The results of the experiments are presented in table 5.

As can be seen from the table, the KSD for the inventive mixtures is 1.7, that is, the effectiveness of the joint action is 70% higher than the additive.

table 2
The retention of drugs on glass and plastic plates №№ Sample Name Plate material The concentration of the emulsion,% Retention% 1 Sample No. 1 glass 0.5 47 plastic 0.5 78 2 Sample No. 1 glass 0.25 39 plastic 0.25 70,4 3 Sample No. 4 glass 0.5 45 plastic 0.5 77,2 4 Sample No. 4 glass 0.25 39.5 plastic 0.25 69.9 5 Sample No. 10 glass 0.5 54.7 plastic 0.5 89 6 Sample No. 10 glass 0.25 46 plastic 0.25 79 7 Sample No. 11 glass 0.5 52 plastic 0.5 88 8 Sample No. 11 glass 0.25 47 plastic 0.25 82

As can be seen from the table, the retention of samples containing oil in their formulation is 7-8% higher on glass and 9-13% on plastic.

Table 3
Spring wheat test results Example No. Dose, g / ha The death of weeds,% of control Wheat yield, kg / ha 1 300 91 41,4 2 300 91 40.9 3 300 92 41.2 4 300 92 41.9 5 300 91 41.7 6 300 93 42.1 7 300 92 42.3 8 300 92 41.9 nine 300 93 42.7 prototype 300 83 39.8 Dialien 300 84 39.8 Esteron 300 84 38,2

Table 4
The test results of samples in the fight against root species of weeds №№ Name of samples Efficiency in the fight against root shoot weeds,% Productivity, t / ha Yield increase, c / ha Culture Grade Consumption rate on a.a., g / ha butting field sow thistle field bindweed 1 Sample Example 1 92 91 82 35.8 3,7 spring wheat Altai 98 300 2 Prototype (example 1) 75 73 70 33.1 1,0 - "- - "- 300 3 Control without processing - - - 32.1 - - "- - "- - 4 Sample Example 10 97 94 82,2 9.9 2,3 spring wheat Third 300 5 Banvel D * 82 79 65.7 9.5 1.9 - "- - "- 300 6 Control without processing - - - 7.6 - - "- - "- - * Dimethylamine salt of 2-methoxy-3,6-dichlorobenzoic acid

Table 5
Performance Indicators and Coefficients of Combined Action (KSD) of Herbicides No. of examples Active ingredients The ratio of AI The values of SK ₉₀ , mg / m ² KSD Wheat growth inhibition estimated experimental 1 2,4-D + 2-ethylhexyl ether dicamba 7: 1 4.0 2,3 1.74 0 2 2,4-D + 2-ethylhexyl ether dicamba 6: 1 4.0 2,35 1.70 0 2,4-D 2-ethylhexyl ether 4.2 Dicamba 2-ethylhexyl ether 3.0

Claims (2)

1. A herbicidal composition containing, as an active substance, a mixture of 2,4-dichlorophenoxyacetic acid esters and 2-methoxy-3,6-dichlorobenzoic acid, a surfactant and a solvent, characterized in that it contains a 2- mixture as an active substance 2,4-dichlorophenoxyacetic acid ethylhexyl ester (I) and 2-methoxy-3,6-dichlorobenzoic acid (II) 2-ethylhexyl ester in an I: II weight ratio of (6-7): 1 as a surface-active substances a mixture of ethoxylated castor oil (III) and dodecylbenzo calcium sulfonate (IV) at a weight ratio of III: IV, equal to 1 ÷ (1,5-2), and as a solvent naphtha or xylene, at the following content of components, wt.%: 2,4-Dichlorophenoxy 2-ethylhexyl ester acetic acid 35.0-77.0 2-Methoxy-3,6-dichloro-2-ethylhexyl ester benzoic acid 5.0-11.0 Surface-active substance 5.0-7.5 Solvent Rest 2. The herbicidal composition according to claim 1, characterized in that it further comprises industrial oil in an amount of 2 wt.%.